i have one thing to say: regular expressions.

Generally, people from a *nix background understand what a regexp is and have a basic grasp of the whole concept of pattern matching...

windows doesnt really have a paralell to *nix regexps, so people starting out perl from a windows background are generally more confused by regexps than seasoned *nix people...

perl was/is heavily influenced by unix command line tools that make heavy use of regular expressions... so i'd say that, in general, seasoned linux people probably pull less hair out than windows people when they first encounter regular expressions in perl... :)